JENKINS AND Cartison, Nervous Impulse in Worms. 277. 
TABLE IX. 
Summary of experiments on Lunice sf. 
Postero-anterior rate. 
No. of No. of records Length of f 
; Se 5 Rate in cm. 
experiment Distal | Proximal cord in cm. 
I 2 | 2 9 473-4 
z 3 3 4.5 409.0 
3 14 | 12 5-7 474.8 
4 13 12 | 13.0 520.0 
Mean rate: 466 cm. per sec. 
Standard deviation: 41. 
Coefficient of variability: .o9. 
Nereis sp. 
This species is very common at this point. It is found 
under rocks and crevices, attaining a length of 15 cm. The 
posterior third of the body is too weak and fragile to raise the 
lever, hence the antero-posterior rate was not determined. Un- 
less it was first decapitated the conditions of the experiment 
invariably threw the worm into violent contractions by which 
it broke into pieces. The activity and irritability of this worm 
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Fig. ro. Nereis sp. Postero-anterior. Length of nerve cord between distal 
and proximal electrodes: 12 cm. Rate: 133.2 cm. persec. Time: 50 
d.v. per sec. 
is much the same as that of Eunice and Glycera. However it 
does not respond to single induction shocks as regularly as 
does Glycera. A single shock applied to the cord posteriorly 
produces a contraction anterior to the point of stimulation, the 
distance to which the contraction extends depending on the in- 
tensity of the stimulus. Still, the contraction does not always 
reach the head even with a high intensity of stimulus. The 
interrupted current is more sure of producing this effect. 
